i) Field of the Invention
This invention relates to a novel fluorene derivative, 9,9-bis(3,5-diphenyl-4-hydroxyphenyl)fluorene and a novel transalkylation process for its preparation, as well as to novel poly(arylene ethers) derived from the novel fluorene derivative, and a process for the preparation of the poly(arylene ethers).
ii) Description of Prior Art
Poly(arylene ethers) are an important class of high performance thermoplastics having an attractive combination of chemical, physical and mechanical properties. Commercially available poly(arylene ethers) are used in a variety of applications as moulding resins, coatings, adhesives and ultra-filtration membranes; in addition poly(arylene ethers) have attracted considerable attention as potential matrix resins for advanced composites in aerospace vehicles.
A disadvantage of many known poly(arylene ethers) is that they lose their properties at relatively low temperatures because of their low glass transition temperatures, and in some cases they have poor thermo-oxidative stability.
U.S. Pat. No. 4,889,909 describes certain high temperature-resistant poly(arylene)ethers which are amorphous and which are thermoplastic.
Semi-crystalline poly(arylene ethers) have been described in Polymer, 1988, Vol. 29, pages 358 et seq P. M. Hergenrother et al; and both crystalline and amorphous poly(arylene ethers) have been described in Polymer Prep. 1985, Vol. 26, page 174 et seq, P. M. Hergenrother et al.
The acid-catalyzed condensation of carbonyl compounds, for example, ketones, with phenols to yield bisphenols is well known. If the ketone is aromatic, the dihalide derivative is employed in place of the ketone.
J. Org. Chem. Vol. 38, No. 8, 1973, 1621-1622, J. L. Webb et al confirms that 2,6-diphenylphenol will not react with acetone to form a bisphenol, but that under strong acid conditions a pyran is formed. U.S. Pat. No. 3,723,456 exploits the reaction to produce pyrans.